Her appointment was announced on Wednesday by the library Board of Trustees and Mayor Richard Alcombright.
"Mindy will be a great addition to our public library and our city team," said the mayor in a statement. "She brings great experience, a working knowledge of our library and a passion for this work. I could not be more pleased with Mindy's acceptance of the position."
He thanked the trustees for their efforts and Robin Martin for "her hard work and dedication as interim [director]."
Hackner declined comment when contacted Wednesday, demurring until she officially takes the post on March 17.
In the press release, she said she was excited about the opportunity and pledged to work with current staff and trustees to "continue providing the best library service in the heart of the city."
Martin has been interim director since August 2013; previous director Rick Moon left last summer to run the newly renovated library at McCann Technical School.
Hackner received her bachelor of arts in English from the University of Massachusetts and her masters of library science from State University of New York.
She has extensive knowledge of library operations and was webmaster, circulation and children's librarian in Williamstown.
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